There are many instances in which precious metals or toxic metals are suspended in a material. There are many bodies of water (e.g., lake beds, river beds, sewage, and sludge) in which precious metals or toxic metals are suspended within silt and water forming, for example, sludge. Likewise, effluent from certain mining or processing operations includes some concentration of precious metals or toxic metals such as the metals that are being mined. With prior technology, it was not cost effective to extract the precious metals or toxic metals from these material so the material remains, in some cases, polluting the area around where the material is present (e.g. cadmium and lead suspended in sludge in a lake bed).
Often there is value to these materials if sufficient quantity is extracted from the sludge, but prior systems were incapable of a cost-effective extraction of precious metals or toxic metals, especially when such precious metals or toxic metals are suspended in low concentrations.
What is needed is a system that will extract metals that are suspended in a material such as sludge or water.